A collection of reagents and other associated materials intended to be used for the qualitative and/or quantitative detection of immunoglobulin A (IgA), immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies to multiple species of Legionella in a clinical specimen, using a fluorescent immunoassay method. Legionella species intended to be detected may include Legionella pneumophila, L. longbeachae, L. jordanis, L. bozemanii, L. gormanii, L. micdadei, and L. dumoffii which are associated with pneumonia-like respiratory infection and Legionnaires' disease.